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How do citizens who live in municipalities that are in ‘news deserts’ find out about what is happening where they live? Developed in the United States and investigated in Brazil and the United Kingdom, the concept of ‘news deserts’ has aroused the curiosity of scholars and agents involved in the development of public policies in Europe, with the mapping of such areas being the target of a European Commission Call for Proposals to support local media in news-poor communities. The phenomenon of news deserts results from a systemic and wide-ranging crisis that journalism as a whole is facing, with profound effects on the local media. A ‘news desert’ is defined as a community without a local newspaper and also a community whose inhabitants face significantly reduced access to news that feeds the foundation of local democracy. One of the first mappings carried out in Europe, the News Deserts Europe 2022: Portugal Report, revealed that 25.3% of Portugal's municipalities did not have media outlets based in the municipality about which they produced contents, a phenomenon linked to more isolated communities with lower economic activity and smaller. But people somehow obtain information in these news deserts. Studies show that much of the local information in those regions is accessed through social media, such as Facebook pages and groups, which can be sources of disinformation and manipulation. When there is no media covering local affairs, communities are left without a point of reference.

This study explored the effects of incorporating RA into geopolymer concrete, particularly examining its performance under ambient and elevated temperatures ranging from ambient temperature to 700°C.

The current study incorporates RA to replace conventional aggregates in the mix, with replacement levels ranging from 0 to 50%. Each mix designation is identified by a unique ID: RA0, RA10, RA20, RA30, RA40 and RA50, representing the percentage of RA used. The alkaline-to-binder ratio adopted for this study is 0.43.

The compressive strength starts at 50.51 MPa for 0% RA and decreases to 39.12 MPa for 50% RA after 28 days. It is highest with 0% RA and diminishes as the RA content increases. All mixes show a slight increase in compressive strength when heated to 100°C. However, the compressive strength starts to decrease for all mixes at 300°C. At 700°C, there is a drastic drop in compressive strength for all mixes, indicating significant structural degradation at this temperature.

The study evaluates the qualitative impact of RA on the properties of geopolymer concrete when exposed to severe temperatures. The experimental setup included several tests to assess the concrete mixes' mechanical properties and responses. Specifically, the researchers conducted compressive, flexural and split tensile strength tests.